Effect of Ischemia-Reperfusion on Heat Shock Protein 70 and 90 Gene Expression in Rat Liver: Relation to Nutritional Status

Heat shock proteins are intracellular proteinsassociated with a generalized response of cells tostress. The purpose of this study was to assess RNAlevels of heat shock protein 70 and 90 in fed or fasted rat livers during ischemia-reperfusion.Northern blot analysis of heat shock proteins wasperformed. Adenosine triphosphate and glutathione wereassessed. In baseline conditions, livers of fasted ratsshowed a twofold increase in mRNA for both heat shockproteins and 38% and 43% reductions in adenosinetriphosphate and glutathione, respectively, whencompared with organs from fed rats. After ischemia,livers of fasted rats presented a twofold decrease inheat shock protein mRNA, while no changes were observedin livers of fed rats; reduced glutathione and adenosinetriphosphate decreased 55% and 50% in fasted livers and 25% and 20% in fed organs,respectively. After 120 min of reperfusion, heat shockprotein mRNA rose threefold in fasted livers, while aslight decrease was observed in the fed group; reduced glutathione and adenosine triphosphate returnedto 65% and 70% of baseline values in fasted livers and85% and 90% in fed organs, respectively. In conclusion,the nutritional status affects heat shock protein expression determined by reperfusion. Thereduced antioxidant status leading to increasedoxidative stress could be the mechanism underlying thephenomenon.